Electric coffee mills



J. FRANCESCH ELECTRIC COFFEE MILLS Filed Dec. 6, 1954 June 11, 1957 INVENTOR ATTORNEYQ ELECTRIC COFFEE MILLS Jose Francesch, Barcelona, Spain Application December 6, 1954, Serial No. 473,368 Claims priority, application Spain December 7, 1953 2 Claims. (Cl. 241-168) This invention relates to improvements in electric coffee mills, and its principal objects are to render their employment more practical and to reduce their cost.

One of these improvements relates to fabricating the parts forming the framework or housing of the mill of a dielectric plastic material, in order that the guides of the current brushes, which slide against the commutator of the motor, can form an integral part of the general framework, and whereby the partition which closes the grinding pit serves also as a cover for the guides of the brushes.

The different pieces of plastic material are connected with one another so that the motor is placed with its armature or rotor in a vertical position in the normal position of use, and its axle is supported by a bearing only at its upper end, while the countersunk lower end of the same rests on a steel ball floating upon a nylon disk adjusted by means of an adjusting disk of metal or some other material, the axial pressure being regulated by means of a screw.

Another utilitarian improvement lies in the fact that electric plug connection tips or pins protrude from the housing or framework of the mill for its direct connection with the conventional electric appliance outlet without using any connecting cord or wires. As a very short time is needed for coffee grinding, due to the great speed of the motor and to the employment of quick-acting chopping knives, it is more practical for the user to approach and couple the mill with the electric outlet than to utilize a flexible connecting cord joined to the apparatus.

' The direct electric coupling avoids the troubles provoked in most appliances by the use of a flexible connecting cord. By eliminating the flexible connecting cord, the damages are avoided which have been caused by the badcondition of the cord in consequence of the successive bending or rolling and unrolling-operations and stretchmg.

Another practical feature is due to the fact that the housing of the mill has such a configuration and dimensions that it can be held in one hand only, the hand grasping it firmly by its base which thus acts as a handle.

In order that the mill can always be coupled to the outlet while being held in the vertical position, even though the female apertures of the electric outlet are not oriented always in the same position, it is planned that the plug pins protruding from the apparatus are mounted on a rotary plate which allows one to arrange the tips in either the horizontal or vertical position, according to the arrangement of the female apertures of the appliance outlet with which the connection is to be established.

Another improvement in the employment of the mill lies in the fact that the cover, which covers the grinding pit and prevents the projection of the grains to the outside, serves at the same time as a container for measuring out the coffee before grinding and which receives it afterwards; for this last operation it is sufficient to invert the mill and to separate it from the cover, which is formed to provide an inner concavity acting as the collecting container. With the object to facilitate the handling of the 2 cover, both when separated and also in the inverted position when it sets as the base of the mill, symmetrically arranged flies or webs on the exterior surface of the convex cover are provided, which make it possible for it to stand firmly on a plane and serve besides as handles when twisting or untwisting the cover.

In the accompanying drawings forming an integral part of this specification, a practical embodiment of the invention is shown as an example.

In the drawings:

Fig. 1 is a vertical sectional view of the electric cofiee mill, showing the vertical suspension of the motor axle and the manner of assembling and adjusting the brushes of the motor,

Fig. 2 is a perspective view of the electric coffee mill being supported with the hand and about to be connected directly with the electric appliance outlet or receptacle,

Fig. 3 is a perspective view of the mill with the cover removed, and

Fig. 4 is a perspective view of the cover alone, supported on the flies or legs, i. e. in the use of the lid as a container for the coifee to be ground or which has been ground.

The said improvements, which are the object of this invention, will now be described in connection with the drawings.

' serving besides as the cover for the guides of the brushes.

The grinding pit is delimited between the said cover closure 2 and the exterior convex cover 3.

The hollow body 1 is closed at its lower end with a screwed cover 4 of a soft plastic material which supports the lower end of the motor axle 5 and supports at the same time the entire motor by pressing against the lamination stock or field structure 7 through a disk 4' of appropriate material between the cover 4 and the field structure or stator.

The brushes 8, 8' guided by horizontal partition bars 1 at the top of the tubular body 1, rub against the motor commutator 6 and, at the ends of said guides, the supsupported by a single upper bearing 11, which bears laterally against a housing 11' forming an integral part of the body of the mill or of its general framework, with interposition of a concave formation which forms a selfaligning bearing. The bearing 11 is maintained in the appropriate position by action of a spring 12.

The lower end of the motor axle floats upon a nylon disk 14 into which a steel ball 13 is fitted, the nylon disk being adjusted by means of an adjusting disk 15 of brass or other material whose pressure thereagainst is regulated by a screw 16 threaded in the lower cover 4 which therefore has in its centre a boss or gudgeon 4" for housing the adjusting screw 16 and the disks. The small cover plate 17 serves to avoid the accidental disarrangement of the adjusting screw 16.

Once the different pieces arranged in the previously described way are assembled, the motor closed off by screwing down the lower cover 4 only, all the pieces find themselves in the correct position without the necesconfiguration given to the said part of the body in the mill.

The upper part of the handle 1, which widens in the form of a cup, is so shaped that it has a laterally protruding portion 21 serving as the base of the insulating plate 20 from which emerge the plug tips 19 which extend beyond the maximal perimeter of the assembly in order that when plugged in the body of the mill remains a little separated from the electric receptacle which has to feed the motor. The tips 19 are given an appropriate length and form, in order to establish the electric connection by approaching and supporting the mill with the hand against the receptacle B, as it is convenient to keep the mill connected and positioned by the tips themselves, due to the short time necessary for grinding and to the characteristics of the motor.

The receptacle as installed sometimes has its female apertures in horizontal aligned position and sometimes in a vertical line, and it is therefore understood that the tips 19, which are conveniently connected with the brush holders or terminals of the motor, are placed upon an insulating plate 20 arranged on the flat end of the protruding part 21, so that the position of the plate 20 can easily be inverted in relation to the plane of 21, in order that the tips 19 can emerge from the said plane in vertical or horizontal position so as to correspond to the positions of the apertures of the outlet receptacle. It is understood that the said position adjustment of the tips 19 need only be efiected when the mill is to be connected with a receptacle in a position ditfering from the usual one, and in general it need not be changed, once given the necessary position. It is evident that the position change of the tips does not alter the connection with the supply terminals of the motor.

On the convex surface of the cover 3 some symmetrically distributed flies or webs 18 are embodied which besides facilitating the holding by serving as handles, enable its stable support on a flat surface.

In order to fill and empty the mill, the position of the cover supported by the flies 18 is inverted, and it is suflicient to turn the handle 1 over, in order to untwist and separate it from the cover 3; for this purpose the closure 2 forming the bottom of the grinding pit has on its inner border a thread corresponding to that which is on the exterior border of the cover 3.

The receiver forming the inner concavity of the cover 3 receives the coflee and has parallel marks 3' which indicate determined capacity, weight or volume and serve to measuer the coffee before and after grinding.

After arranging the required quantity of coffee grains in the concavity of the cover, e. g. while in the Fig. 4 position, the body of the mill is threaded on it in its inverted position, and on plugging in the apparatus in the vertical position, the coffee grains are ground by the chopping knife 22 turning with great velocity and placed on the upper end 10 of the motor axle which emerges from the bottom of the grinding pit.

The cover 3 impedes the projection of the grains outside during the grinding and, as it is preferably of a transparent material, it is possible to see when all the grains have been ground.

On inverting the mill, when disconnected, the ground coffee lies in the cover concavity 3, and it is sufficient to remove the body of the mill in order thereupon to dispose of the cofiee contained in the receiver formed by the cover.

It is understood that the form and exterior lines of the mill, as well as the construction details which. change no essential characteristics of this invention, can be varied or modified at will.

What is claimed as new, is:

1. In an electric coffee mill, a generally cylindrical motor housing forming a handle portion, a motor in said housing, a partition in said housing forming one boundary of a grinding chamber, a knife driven by said motor disposed in said chamber, a bearing for the motor shaft secured adjacent said partition, a closure fastened in the opposite end of the housing, an adjustable thrust. bearing between said closure and the end of the motor shaft, and an electric connection plug extending from the upper end of said housing.

2. An electric coffee mill comprising a generally cylindrical motor housing, a commutator motor in said housing, a partition plate integral with said housing, guides on said partition plate, motor brushes in said guides cooperating with the commutator of said motor, a bearing for one end of the motor shaft secured adjacent one end of said housing, a closure fastened in the opposite end of the housing, an adjustable thrust bearing between said closure and the other end of the motor shaft, and an electric connection plug secured to and extending from said housing.

References Cited in the file of this patent UNITED STATES PATENTS 959,606 Ramstad May 31, 1910 1,359,208 Viers Nov. 16, 1920 2,203,672 Chester June 11, 1940 2,301,851 Boerger Nov. 10, 1942 2,692,126 Schwaneke Oct. 19, 1954 FOREIGN PATENTS 5,106 Germany May 21, 1879 141,147 Australia May 8, 1951 978,418 France Nov. 22, 1950 

